2. It's low efficiency. It requires large areas of land.
No it doesn't, all it takes is the roof of the house you already have covering up a bit of land. Come to think of it, the garage roof and the patio roof and the pergola roof are all sitting there hoping to be used for something other than contaminating our lakes and streams with washed off asphalt.
Here's a good idea, cover all the asphalt roofs with solar panels so we don't have to replace those wonderful asphalt roofs so often. Anything with the word asphalt in it is not good.
It is true that if we put large solar arrays across the ground they would cover large areas of land. So far, with the larger ground mounted arrays I am familiar with, they are on ground not much good for anything else anyway. Like the one in the buffer strip of the freeway.
Considering just efficiency, without the land part, solar collectors are not the most efficient things in the world. Most solar panels are considered to be about 15% efficient. But, this is getting better all the time. Some panels have achieved over 20% efficiency.
To cheer me up after thinking about the low efficiency, I just think about that 600 horsepower diesel engine blowing black smoke as it pulls another load of coal out of the ground.